The wild and captive koala population of the Mt Lofty Ranges in South Australia has a high level of renal dysfunction in which crystals consistent with calcium oxalate have been observed in the kidneys. This study aimed to describe the pathological features of the renal disease in this population, confirm the composition of renal crystals as calcium oxalate, and determine whether any age or sex predispositions exist for this disease. A total of 51 koalas (28 wild rescues, 23 captive) were examined at necropsy, of which 28 (55%) were found to have gross and/or histological evidence of oxalate nephrosis. Histopathological features included intratubular and interstitial inflammation, tubule dilation, glomerular atrophy, tubule loss, and cortical fibrosis. Calcium oxalate crystals were demonstrated using a combination of polarization microscopy, alizarin red S staining, infrared spectroscopy, and energy-dispersive X-ray analysis with scanning electron microscopy. Uric acid and phosphate deposits were also shown to be present but were associated with minimal histopathological changes. No significant differences were found between the numbers of affected captive and wild rescued koalas; also, there were no sex or age predispositions identified, but it was found that oxalate nephrosis may affect koalas <2 years of age. The findings of this study suggest that oxalate nephrosis is a leading disease in this koala population. Possible causes of this disease are currently under investigation.

This study investigated the relationships between the density of Meissner's corpuscles and the dermatoglyphic characteristics of human fingers. Dermatoglyphic prints and tissue samples were collected from the index (II) and ring (IV) fingers of 28 cadavers from the Medical School, University of Adelaide. Pattern types, pattern intensity, total ridge count and ridge breadth, were determined for each sample and the density of Meissner's corpuscles established by recording the mean number of Meissner's corpuscles underlying a 10 mm long line on the skin surface. No relationship was found between the density of Meissner's corpuscles and pattern type, pattern intensity or total ridge count. Negative correlations were found for the density of Meissner's corpuscles with both ridge width and size of fingers. Males were found to have significantly larger fingers, larger ridge breadth, and a lower density of Meissner's corpuscles per 10 mm compared with females. However, there was no difference between the total number of Meissner's corpuscles per finger in males and females. No significant differences were found in either the density of Meissner's corpuscles between antimeres or between the index and ring fingers. These results suggest that for both the left and right hand in males and females, there is a similar number of Meissner's corpuscles for both the index and ring fingers.

The aim of this review is to examine the relationship between genetically modified (GM) crops and health, based on histopathological investigations of the digestive tract in rats. We reviewed published long-term feeding studies of crops containing one or more of three specific traits: herbicide tolerance via the EPSPS gene and insect resistance via cry1Ab or cry3Bb1 genes. These genes are commonly found in commercialised GM crops. Our search found 21 studies for nine (19%) out of the 47 crops approved for human and/or animal consumption. We could find no studies on the other 38 (81%) approved crops. Fourteen out of the 21 studies (67%) were general health assessments of the GM crop on rat health. Most of these studies (76%) were performed after the crop had been approved for human and/or animal consumption, with half of these being published at least nine years after approval. Our review also discovered an inconsistency in methodology and a lack of defined criteria for outcomes that would be considered toxicologically or pathologically significant. In addition, there was a lack of transparency in the methods and results, which made comparisons between the studies difficult. The evidence reviewed here demonstrates an incomplete picture regarding the toxicity (and safety) of GM products consumed by humans and animals. Therefore, each GM product should be assessed on merit, with appropriate studies performed to indicate the level of safety associated with them. Detailed guidelines should be developed which will allow for the generation of comparable and reproducible studies. This will establish a foundation for evidence-based guidelines, to better determine if GM food is safe for human and animal consumption.

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Oxalate nephrosis is a leading disease of the Mount Lofty Ranges koala population in South Australia, but the cause is unclear. In other herbivorous species, a common cause is high dietary oxalate; therefore this study aimed to determine the oxalate content of eucalypt leaves. Juvenile, semimature and mature leaves were collected during spring from eucalypt species eaten by koalas in the Mount Lofty Ranges and compared with those from Moggill, Queensland, where oxalate nephrosis has lower prevalence. Total oxalate was measured as oxalic acid by high-performance liquid chromatography. The oxalate content of eucalypts was low (<1% dry weight), but occasional Mount Lofty leaf samples had oxalate levels of 4.68–7.51% dry weight. Mount Lofty eucalypts were found to be higher in oxalate than those from Queensland (P < 0.001). In conclusion, dietary oxalate in eucalypt leaves is unlikely to be the primary cause of oxalate nephrosis in the Mount Lofty koala population. However, occasional higher oxalate levels could cause oxalate nephrosis in individual koalas or worsen disease in those already affected. Further studies on the seasonal variation of eucalypt leaf oxalate are needed to determine its role in the pathogenesis of oxalate nephrosis in koalas.